Minimal external dimensions are considered a desirable characteristic in many contemporary electronic devices. One commonly-used approach to achieving such minimization involves increasing the density in which the internal components of the device are packaged, i.e., placing the internal components in closer proximity to adjacent components and structures within the device.
Increases in component-packaging density typically necessitate a corresponding reduction in the area occupied by the wiring or cabling that interconnects the components. Such reductions are particularly difficult to achieve with fiber-optic cabling. These difficulties arise from the need to avoid any sharp bends in fiber-optic cables. More specifically, a fiber-optic cable cannot be routed in a manner that imposes a curvature which exceeds the minimum bending radius of the cable. Violation of this limit may impair the integrity of the signal transmission, and can damage the cable.
Fiber-optic cables are often joined through the use of adapters. More particularly, adapters are used to support and couple two or more fiber-optic connectors, thereby forming a junction between the cables attached to the connectors. The adapter is frequently disposed on some type of mounting structure, e.g., a backplane. Adapters that are disposed in this manner are commonly known as "backplane adapters." Backplane adapters are typically mounted in a manner that causes the adapter (and the corresponding connectors) to protrude from both sides of the mounting structure.
FIG. 1 illustrates a backplane adapter 10 installed on a backplane 11 in the above-noted manner. A first connector 12 and second connector 13 are disposed within the adapter 12. A fiber-optic cable 14 and a fiber-optic cable 15 are attached to the connectors 12 and 13, respectively. The cable 14 has a minimum bending radius 16 and the connector 12 has a length 17. The adapter 10 straddles the backplane 11, thereby causing the connector 12 and the cable 14 to protrude from a rear surface 11a of the backplane 11. More specifically, the connector 12 and the cable 14 protrude in a direction normal to the surface 11a by a distance 18.
A curvature is imposed on the cable 14 as it exits the connector 12. The curvature equals the minimum bending radius 16, and extends through an arc of about 90 degrees. Hence, the protrusion distance 18 is equal to the connector length 17 plus the minimum bending radius 16. Reducing the protrusion distance 18, without decreasing the connector length 17, would require imposing a curvature on the cable 14 that exceeds the minimum bending radius 16. Hence, the noted value represents the lowest level to which the protrusion distance 18 can be reduced using this particular mounting configuration.
The cable 14 is shown in FIG. 1 as being routed between the backplane surface 11a and an adjacent structure 19, e.g., a panel of the electronic device in which the backplane 11 resides, or another circuit substrate. As is evident from the figure, the protrusion distance 18 represents the minimum required clearance between the backplane 11 and the structure 19. Hence, any reduction in the protrusion distance 18 will allow the backplane 11 to be positioned closer to other components such as the exemplary structure 19. Reducing the spacing requirements for the backplane 11 will facilitate increased component-packaging densities in electronic devices in which the backplane 11 is utilized. The present invention seeks to achieve this goal.